Improvement in kilns for pottery



72- sheets-Sheet R. BOOTH. P'ottery Kiln. y'

Patented Aug'. 31, v17852..

UNITED STATES i ATENT Fries;

GEORGE ROBINS BOOTH, OF HANLEY. ENGLAND.

iMPRovEMENT iN KlLN-s FOR'POTTERY.

Specification forming part of Letters Patent No. 9,230, dated August 31,`1852.

provements in the Mode offApplying ileat to the Burning of Pottery,Bricks, Tiles, Pipes, and other Articles of Earthenware, Clay, or

other Similar Plastic Materials, and for Ilardening on of Printed vvareand I'do hereby declare that the following is a fulland exactdescription of my said invention-that is to say:

My improved mode of applying ,heat from various combustibles relates tothe drying and burning of pottery of all kinds, bricks, tiles, pipes,and other articles of clay or similar plastic materials; and itconsists, principally, in the construction and arrangement of the hearthor fire-places, lues, chambers, dsc., in which the combustibles arcemployed for the purposes of generating heat and the application thereofto the aforesaid manufactures.

The object of my invention is by an improved mode Of applying heatfroinvarious combustibles to the above-named purposes, first, to elect asaving otfuel; secondly, a

diminution of the losses sustained in the articles While being burned,thirdly, to lessen the ordinary wear and tear of the kiln;

fourthly, to insure greater regular-it;` in the heat.

, This improved mode consists in the peculiar construction of the partsconstituting the hearth or fire-place which contains the fuel; in theconstruction of the ovens, chambers, or kilns for coniining the heatwhen evol.\ ed from the hearth or fire-place; in the construe-m tion ofthe apertures, llues, and tubes for the passage of the heat from thehearths to the said oven, chamber, or kiln, and, lastly, in theconstruction of the apertures` lues, and vents for the iinal exit ot thehot air, smoke, and gases.

Such being the nature and object of the invention, I will proceed todescribe the means ot carrying the same into practical effect,`and

for this. purpose'l'have attached to these pres-l ents drawings.exhibiting the entire arrange# ments and. construction of the apparatusconstituting thisimproved mode of applying heat and showing itsparticular application, in the first place,`to=firing ovens for pottery,bricks, tiles, dac., and, secondly, for hardening on, enameling, anddrying.

The combustibles I use are coke, charcoal, coal, cannel, peat, or Wood,either separatel y, all together, or variously combined. The hearth isto be built of fire-bricks or of fire-clay only, or of a mixture oflire-proof clay with tireproof substances, which inA this mixed state Icall pisa The fuel 'is to be supplied to the hearth at the top or sides.The chambers,

ovens, or kilns are constructed of Various forms-square, round,'oblong,or polygonal. When a single Ihearth is used,`I prefer placing itin thecen-terof the floor of the chamber, oven, or kiln belou1 the same; butwhen many hearths are required they will have to bc `placed atproportionate distances fromeaeh other. The heat in the chamber, oven,or kiln is not-permitted in its ascent to escape through the chimney orother opening', but is drawn downward by the apertures and fines, whichare placed in the sides'of the chambers and at the bottom thereof. Iirst direct the honi tif Ward the top of the chamber and then io Lescend, so that in its course 'the fiume and heat may become applied toall objects 'within their range.v The apertures through u hich the heatescapes into the vents are placed at or nea:` the floorofthechamberorbelor,v it, 'l'hennrnber and size of the apertures leading intothe lines for the exil of the heated nir, &i-..de pend upon the heatrequired, the d iepaich that is wanted, `the size of the hearth, dwf.,and especially upon the quantity of t'uel which is used. The verticalfiues are placed on the exterior or within the interior of the walls ofthe. chamber or Within the chamber, as may be *Ln-eferred. They are onlyrequired to be of such a height above the top of the chamber as willplace them a few feet (on thc out side) above the crown of the ovenwith-nbut tlrcy may be carried and collected into one chimney in anydirection or be lett open.

In the drawings hereto annexed I show the application of this inventionto the purposes of firing or burning and 'dryingchina and earthenware,coarse ware, brieks,.tiles, the., in

their various stages of manufacture.

Similarletters ot reference are marked upon corresixnnling parts in eachot the figures.

,Figure l .is a sectional'elevation of apotters oven or a brick, tile,and coarse ware kiln. A is the ehmnberoroven, wh ich may becit-herround, square,-'0blong, or polygonal; B, the hearth; C, thefire-bars; D, the ash-pit; E, the position ot the feeding-door, which ismade air-tight; ll, the door ot the oven; l, apertures leadin from thechamber A to the vertical dues .l J, the vertical. fli'les'leading tothe vents K; U, a tube in thecenter of the cha-mber to carry up the bulkot heat into theupper region, the holes in the sides of which may beclosed when seggars f or cases are not used; N, the gas-tube above theoven or chamber. This tube is kept open until the tube )l becomesred-hot, whereby any light gases collected pass through it; 0,1;he wallot' the chamber, built of pise or of brick; P, the arch or covering ofthe chamber ha\4` i ing no aperture through it, except the small tube R,the tube leading` from the hearth into the chamber. S are tubes or finesplaced at the iront, back, or sides, with openings left on the outsideof the oven. These are opened and closed, as required, by small doors atT,

through which the air passesin to the chamber U," which, being extendedall around the hearth and connected therewith by the openin Y Y, supplyair to theI hearth. W lV are fines for the admission of aporiion of theheat from the hearth to bring up the heat at the lower part of the kiln.

Fig. 2 is a horizontal section of the same oven. showing the positionand size of the fines, apertures, hearths, ovens, the.

'The method of tiring and using the said oven for pottery or for bricks,tiles, &c., is as follows: The seggars, containing the china andearthenware, are placed in the usuall manner and the door ot' thechamber is made close by building it up or otherwise closing it. Thehearth is then charged with coke or charcoal, coal, or wood, or any otthem combined, and this fuel is ignited at' the top or bottom. Then itisburned down the hearth is parftlially refilled and thecontents of thehearth. again allowed to burn down. As the heat of the oven increases,the fire-chamber is found more capable of consuming the'smoke and morecoal may be advantageously em ployed, but if the chamber is tnll ofsteam a sutiieientl supply of coal has been already used. lVhenever theflame ceases a further' supply of fuel must be added, and thus theprocess be continued until a sutlicient heat is obtained. Furthermore,Iwhenever a fresh supply of fuel is added, air must be admitted into thespace above the hearth through V V to mix with and ,ignite the smoketill the quantity admitted .is sufficient to cause conf pletecombustionA If' a v large quantity of coal be used,'then a much largeringress 'of air m ust be admitted over and into the hearth.

The samedgnres and drawings will serve steam to escapo.

to represen-t the application ofY my invention;

'to the process of hardening on, as it 'is termed in potteryAmanufactures, vwhich consists in dissipating the oil which is used inthe process of printing the ware, whereby itv is prepared for` thesubsequent processes `of dipping and of glost or glazed firing. l

The follow' ig is the manner in which my improvedv mode of direeting'theheatA to such purposes is applied. 'lhe chamberA (but of less dimensionsthan in drawingssayga cube. of seven feet) or any other chamber or kilnot' a more convenient form or size may be employed, and as a low heatonly is req'uiredfor this purpose (say the te'mperatureat which. leadmelts) either coke, cinders, charcoal, or peat, or any other suchcombustible sub stances as do not emit smoke in combustion are used. Thebrick tube M, above the top of the hearth seen in the drawings, Eig-1,may therefore be dispensed with, so as .to allow` more available room inthe chamber or kiln, and instead thereof a round or square box made ofeartln-nware, about two or three feet in heightiand square, with aperforated top to the same, maybe substituted', ,on-V which also may beplaced some .broken pitchers to collect an)` dust that may pass throughthev holes at the'top of the ease. I j To regulate the hardening-onchamber-,1I make use of what I-terma vt-hermo-lm-"erI toregister therequisite hea-t. This i`nstru-f ment, which is well known in the'artsandj not necessary to be represented, is tlg-us "corrv str ncted: A leveris placed on the top lot' the chamber, having at one end a rodyor Wirevdescending into the chamber. To /ths a ladle'` is attached, perforatedwith holes'. The other end of the lever is balanced with a weight on theontsideof the kiln. Two flues placed in the side walls of the kiln onthe.; right hand, and on the left with apertures about three inches indiameter and eighteen., inches from the top of the chamber. At the vtopof these vent-s dampers may be a'ixed. These vents'. are to permit thesteam which rises from the ware to be carried off more Y readily rlhechamber or kiln is fitted-'up with iron shelves, or .with iron basketsor boxes, to contain the ware, and an iron' door closes up the chamber;or the doorway may be bricked up and coated overin the usual way. A Themode of using the kiln is as follows: Having filled the kiln with ware,`(except over y the lire-box. t'or about one foot high and at. the

door,) a ,pound of lead is placed in thev ladle of the thermo-lever" andbalanced at the other end.- Then about eight bushels of coke or cindersare placed in the heartlrand igniteth The front ol the kiln is now set'in and the door partially closed. Afterward, when the steam hasdisappeared l'rom the ware, the door is fully closed and the two sidevents also, (except within an inch,) leaving the vent (marked N) opentoallon any remaining Simulianeoi'sly with the sgae a fall ot' the armof the thermo-lever on the outside of the chamber (owing to the leadbeing molten) the process of hardening on is completed. The dampers onthe two side vents are then closed and the ware is allowed to cool,which when done the door ma be opened and the ware removed.

Further', I employ this improved inode of applying heat to firingenameled ware. which consist-s in burnin g ortiring the colors or goldwhich have been painted or printed on the glaze, and enabling the latterto admit of bein g burnished. For this purpose I proceed to adjust thekiln Fig. l in the following manner, or I take a kiln of some othershape, but after the same mode of construction as Fig. l, and iii it upwith an enameling box or case, as described below, which is placedwithin it, resting it upon a brick frame-work that is made to encirclethe top of the hearth, and thus forms an inclosed space round the top'ofthe hearth. The size of the case is adapted to the qintntity of ware tobe tired thereon and is made of iron,'flirebrick, orquarrics after themanner of making the linings for the common enamcling-kilns. The tube inFig. l is raised up to and passes through the top ofthe case; or,insteadot' one tube, a number of tubes, less in size than the center one, are

placed in a similar manner in different parts,

of thecase. The heat, when supplied, will thus have a direct coursethrough the tubes, and, passing over the top ofthe case, will dcscenddown the outside thereof, and will thus heat the whole kiln. ri`he widthof the passage of the heat between the case and the outer walls of thekiln Fig. l is regulated bythe size of the case itself, which thcexperienced workman will knowhow to regulate. `Finally, after the heathas descended to the bottom of the case or framezwork upon which itstands it will. pass into the ventsl in the saine manner as it does inthe plan Fig. 1 for firing pottcry. the tiresl are also the same asthose given under v the direction of ti ring pottery, the heat beingadjusted to the degree requisite for the process. In all other respectsthe same plan of burning is pursued which is followed in endrying of theclay for marketable purposesat the pits. for drying simple or compoundvbodies, and for drying other materials and articles used in and requiredfor the pitting trade and general drying purposes. l'hi.`

portion of in) invention may therefore properly be termed a part of theprocessof firing 'and most economic principle.

'lhe fuel-hearth and mode of feeding p or burning, being only temperedby the dii'- ferent amount of heat required either in indu'ration ordesiccation. It maybe expedient, therefore,l in many cases as a matterof economy to separate the drying processes from the burning."

Drying-stoves then become an appendage to-such operation. My inventiontherefore would be incomplete without a suitable plan foi-drying wasgiven, particularly so since the invention itself aifords all requisitefacilities for erecting and constructing dryingstoves, which I nowproceed to describe. The improved and economic drying-stove may beformed after the manner of a large kiln or chamber like Figi; or achamber of any other shape or size, upon the same principle, may befitted up with iron doors to the entrance and with iron shelves againstthe walls if much heat is required, upon which pottery bricks, tiles,pipes, or any other goods can be dried. A hearth of small dimensionswill only be required. Another modification upon these principles willbe th us: By placing au apparat-us like the ire-box described, for thehardening -kiln in the eenier of a room, erected upon the mode lastdescribed, and like Fig. l in principle, all `kinds of pottery and goodsmay be dried thereon with economy and effect, this plan being simply thelnlrdeniugkiln applied to drying purposes. having a large chamberinstead of a small one, and rcquiringalcss degree of heat.

Lastly, if a kiln or stove like Fig. l were made of iron plates aboutseven feet size cube, with a hearth within it like l and placed in alarge room or chamber of one thousand cubic feet or more and fitted upwith shelves, trellis, tbc., as before named or as otherwise suitablefor th-e purpose in hand, there would be constructcd anotherdrying-stove upon a useful In 'this last case the vents or chimneysattached to the iron stove, and marked K in Fig. must be continued untilthey-pass through the roof of the drying-chamber, for they must becarricd to and through orfint'o thc walls of the said chamber in some'convenient direction. Thus in the firsttwo cxampcs of thesedrying-stoves the heat would be applied directly to the goods tor thepiirpose of desiccation as in the plan of 'firing, and in the lat-terlcases the drying process will be conducted by 'the radiation of heatalone. Thus these different plans constitute a variety of modes ofdrying apparatus suitable to the quality, 11ature, and state of everyarticle that may require such processes and treatment.

Having thus described the nature and objects of my saidimprovements,together with the manner of carrying the same into effect,

I have to add that what l claim as myinvention, and desire to secure byLetters Iatcnt,

ism v The arrangement of. the lire-hearth below the oven-bottom andprovided with suitable apertures for the admission ol' air to regulateIthe combustion, substantially as described, at or nem' Jthe top for thedischarge of gases when @his is combined with the oven or heatorsteam,all substantially as herein described, ing-chamber, providedwith L tubeor the and for the purpose specified.

equivalent thereof, :1s-specified, for discharg- 1 n s x ing the heatabove the bottom of the oven GEORLR IO'bmb bOOrl H' and diffusing it inthe oven, and also provided with outlet flues or apertures at or nearthe bottom, and with apertures or tubes lVitnesses: t

JOHN DAVIS MANCHESTER, JOHN RIDGWAY CALLDENPLACE.

